ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Recent Posts
GFCI's pops in large numbers
by dsk - 09/26/22 04:35 AM
AFCI’s Revisited
by sparky - 09/24/22 09:58 AM
NFPA Price Increase Coming
by Bill Addiss - 09/23/22 02:22 PM
Siemens breakers
by gfretwell - 09/23/22 01:45 PM
What do you look like?II
by HotLine1 - 09/22/22 12:33 PM
New in the Gallery:
240/208 to a house
240/208 to a house
by wa2ise, October 9
Now you know.
Now you know.
by Tom_Horne, September 7
Who's Online Now
0 members (), 38 guests, and 11 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#139213 10/24/03 03:22 PM
Joined: Dec 2001
Posts: 2,497
I found a cool piece of old equipment. It's a fault voltage circuit interruptor intended to detect ground faults. It's got 2 ground connections, 1 for the incoming ground (auxiliary ground) and 1 for the load ground. If there was a voltage between load ground and auxiliary ground exceeding 50V it tripped. It's a 10x10x10cm box, still wired to a long piece of old NYM cable with the colors black, black, blue, grey and red. Auxiliary ground seems to be a long green wire.

#139214 10/24/03 03:31 PM
Joined: Aug 2001
Posts: 7,520
That sounds like the old British voltage-operated ELCB (Earth-Leakage Circuit Breaker), commonly used as the ground fault protection in rural areas in the past ( U.K. Power Systems , diagram #4).

There are still plenty of these in service in this area.

#139215 10/25/03 05:05 AM
Joined: Jul 2002
Posts: 8,423
Likes: 3
These units are still in use over here too.
But our units have an arbitary value of trip @ 25VAC.
Only used in areas, where the basics of the MEN supply can't be met, with respect to Fault currents (Earth resistance/Neutral Return).

[This message has been edited by Trumpy (edited 10-25-2003).]

#139216 10/26/03 11:27 AM
Joined: Aug 2001
Posts: 7,520
These devices used to be the norm across large area of rural England, before PME was extended and before the current-operated ELCB became common-place.

They were required to trip at 50V maximum, but many actually trip well below that threshold. I've seen a few that will trip out on under 10V.

Link Copied to Clipboard

Tools for Electricians
Tools for Electricians

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Member Spotlight
Posts: 201
Joined: April 2004
Top Posters(30 Days)
dsk 3
Popular Topics(Views)
297,396 Are you busy
228,255 Re: Forum
213,158 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5